A "backward equation" is a mathematical expression that is solved by working from the result back to the original values. This approach is often used in algebra to find unknown variables by rearranging the equation. It helps in understanding how changes in one part of the equation affect the overall outcome. In practical applications, backward equations can be useful in fields like finance and engineering, where determining initial conditions or inputs is necessary for predicting future results. By analyzing the final outcome, one can trace back to identify the contributing factors or variables involved in the process.